Variable ratio lever mechanism



9, 1966 R. J. GORSKY 3,264,896

VARIABLE RATIO LEVER MECHANISM Filed July 14, 1964 1N VENTOR.

flan afar; J 65/1451" EA TTORNEY United States Patent 3,264,896 VARIABLE RATIO LEVER MECHANISM Rudolph .ll. Gorsky, Fenton, Mich., assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed July 14, 1964, Ser. No. 382,452 5 Claims. (Cl. 74-516) This invention relates to a variable ratio lever mechanism. Of the many possible applications of this variable ratio lever mechanism, it has been found particularly useful when incorporated in an automotive vehicle to provide a slow rate of initial carburetor throttle opening and a more rapid rate of further carburetor throttle opening.

In many automobiles the linkage between the accelerator pedal and the carburetor throttle provides a straight line relationship between pedal travel and throttle opening. In certain situations, however, such a relationship is not the most advantageous. For instance, when the relationship is properly established for most driving conditions, it proves to be too sensitive for a maneuver such as parking. Because of the sensitivity, vehicle operators are frequently unable to exert the proper control when parking the vehicle, causing too great an acceleration of the vehicle and occasional property damage.

In order to reduce this sensitivity of the relationship between throttle opening and pedal travel and to increase the control of the operator over his vehicle, it has been proposed to include a variable ratio lever mechanism in the throttle linkage which would provide a slow rate of initial throttle opening and a more rapid rate of further throttle opening.

However, such a mechanism has not heretoforeprovided a smooth transition between the initial slow rate and the further more rapid rate. It is an object of this inveniton to provide a variable ratio lever mechanism having a smooth transition between its available ratios. It is a further object of the invention to provide an automotive throttle linkage including a variable ratio lever mechanism having a smooth transition between the available ratios.

This invention, therefore, provides a variable ratio lever mechanism in the linkage between the accelerator pedal and the carburetor throttle. As is customary, a lever is pivoted on the automobile fire wall and connected at one end to the carburetor throttle valve. On the end of the lever adjacent the accelerator pedal, this invention provides a pair of rollers. The undersurface of the accelerator pedal, as it is pivotally depressed, bears first against one and then the other of the rollers. Since the second roller is closer to the pivot point of the lever, an increment of travel thereof will cause a greater increment of travel by the one end of the lever, and thus a greater degree of throttle opening, than the same increment travel of the first roller. Thus, as the accelerator pedal is depressed, the throttle is opened initially at a slow rate and subsequently at an increased rate.

This invention also provides a pliable, resilient roller mounted on the lever between the two previously mentioned rollers. This roller is deformed as the accelerator pedal bears thereagainst in the interval between contact with the first roller and contact with the second roller. The pliability and resiliency of this intermediate roller provides a smooth transition between the two rates of throttle opening.

The details as well as other objects and advantages of this invention are disclosed in the remaining portion of the specification and in the drawing, in which:

FIGURE 1 is an elevational view of the variable ratio lever mechanism as it may be applied in an automotive vehicle between the accelerator pedal and the carburetor throttle; and

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FIGURE 2 is a plan view of the accelerator pedal taken along line 22 of FIGURE 1 and showing, through a breakaway portion, the roller mechanism mounted on the lever.

Referring to the drawing, FIGURE 1 shows an area of an automotive vehicle adjacent the fire wall 10. Located on one side thereof is the engine 12 having mounted thereon a carburetor 14. Located on the other side of the fire wall 10 is an accelerator pedal 16 pivotally mounted, as at 18, on the vehicle floorboard.

A lever 20 is pivotally mounted, as at 22, on fire wall 10. One end 23 of lever 20 is connected by a link 24 to the throttle arm 26 which is secured to the throttle valve shaft 28 of carburetor 14. Lever 20 is biased in a throttle closing direction by a spring 30.

The other end of lever 20 has mounted thereon two firm rollers 32. and 34 and a pliable, resilient roller 36 which are adapted to bear sequentially against the undersurface of accelerator pedal 16.

Rollers 32, 34, and 36 are shown in further detail in FIGURE 2. Rollers 32 and 34 may be made of plastic, and roller 36 may be made of soft rubber. An additional rubber ring 38 may be mounted about a reduced portion of roller 34 to damp any vibration of accelerator pedal 16 against roller 34.

The operation of this variable ratio lever mechanism may be seen in FIGURE 1. During initial depression of accelerator pedal 16, and thus during initial throttle opening, accelerator pedal 16 pivots lever 20 by contact through roller 32. After initial depression of accelerator pedal 16, and thus after initial throttle opening, accelerator pedal 16 transmits further pivotal movement to lever 20 through roller 34. Inasmuch as the effective length of this end of lever 20 is shorter when moved by accelerator pedal 16 through roller 34 than when moved through roller 32, a slow initial opening and a more rapid further opening of the throttle is obtained. The relative rates may be predetermined by appropriate shaping of lever 20 and the undersurface of accelerator pedal 16 and by appropriate spacing of rollers 32 and 34.

As the effective point of contact between accelerator pedal 16 and lever 20 moves from roller 32 to roller 34, it passes across flexible roller 36. Roller 36 is gradually compressed as pedal 16, in contact with rollers 32 and 36, approaches roller 34 and is gradually decompressed as pedal 16, now in contact with rollers 34 and 36, recedes from roller 32. During the instant in which pedal 16 contacts both rollers 32 and 34 and roller 36, substantially all movement of pedal 16 is imparted to lever 20 thruogh the intermediately located roller 36. It will thus be appreciated that the effective point of contact between pedal 16 and lever 30 moves gradually from roller 32 to roller 34, creating a smooth transition between the ratios provided by the spaced rollers 32 and 34.

I claim:

1. A variable ratio lever mechanism comprising a first lever adapted to be mounted for pivotal movement, said lever being adapted to impart movement to another member, said lever having a multiplicity of spaced contact points located thereon, a second lever adapted to be mounted for pivotal movement, said second lever having a multiplicity of spaced contact points located thereon which upon pivotal movement of said second lever successively bear against said contact points on and impart pivotal movement to said first lever whereby a multiplicity of ratios is available for imparting movement to an other member through said first lever from said second lever, and resilient means located on one of said levers adjacent the contact points thereon which upon pivotal movement of said second lever bears against a portion of the other of said levers adjacent the contact points thereon to provide a smooth transition between the available ratios.

2. A variable ratio lever mechanism comprising a first lever adapted to be mounted for pivotal movement, said lever being adapted to impart movement to another member, a pair of relatively firm rollers mounted on said lever near one end thereof, the axes of said rollers being parallel, relatively resilient means mounted on said lever intermediate said rollers, a second lever adapted to be mounted for pivotal movement, said second lever having a surface which upon pivotal movement of said second lever successively bears against one of said rollers, said relatively resilient means, and the other of said rollers and imparts pivotal movement to said first lever whereby a multiplicity of ratios is available for imparting movement to another member through said first lever from said second lever and whereby a smooth transition between the available ratios is provided.

3. In an engine driven vehicle having a throttle adapted to control the speed thereof, linking means connected to the throttle, a lever pivotally mounted in the vehicle and connected to said linking means and adapted to impart movement thereto, said lever having a multiplicity of spaced contact points located thereon, an accelerator pedal pivotally mounted in the vehicle, said pedal having a multiplicity of spaced contact points located thereon which upon pivotal movement of said pedal successively bear against said contact points on and impart pivotal movement to said lever whereby a multiplicity of ratios is available for opening the throttle through said linking means and said lever from said pedal, and resilient means located on one of said lever and said pedal adjacent the contact points thereon which upon pivotal movement of said pedal bears against a portion of the other of said lever and said pedal adjacent the contact points thereon to provide a smooth transition between the available ratios.

4. In an engine driven vehicle having a throttle adapted to control the speed thereof, linking means connected to the throttle, a lever pivotally mounted in the vehicle and connected to said linking means and adapted to impart movement thereto, a pair of relatively firm rollers mounted on said lever near one end thereof, a relatively resilient roller mounted on said lever intermediate said relatively firm rollers, the axes of said rollers being parallel, and an accelerator pedal pivotally mounted in the vehicle, said pedal having a surface which upon pivotal movement of said pedal successively bears against one of said relatively firm rollers, said relatively resilient roller, and the other of said relatively firm rollers and imparts pivotal movement to said lever whereby a slow rate of initial throttle opening, a more rapid rate of further throttle opening, and a smooth transition therebetween are provided.

5. In an engine driven vehicle having a throttle adapted to control the speed thereof, linking means connected to the throttle, a lever pivotally mounted in the vehicle and connected to said linking means and adapted to impart movement thereto, a first relatively firm roller mounted on said lever near one end thereof, a second roller mounted on said lever adjacent said first roller, a relatively resilient roller mounted on said lever intermediate said first and second rollers, the aXes of said rollers being parallel, an accelerator pedal pivotally mounted in said vehicle, said pedal having a surface which upon pivotal movement of said pedal successively bears against said first roller, said relatively resilient roller, and said second roller and imparts pivotal movement to said lever whereby a slow initial throttle opening, a more rapid further throttle opening, and a smooth transition therebetween are provided, said second roller having a relatively firm axial portion and a relatively resilient axial portion whereby vibration of said pedal against said second roller is damped.

References Cited by the Examiner UNITED STATES PATENTS 1,551,493 8/1925 Lawson 74513 2,436,897 3/1948 Nut 74-516 2,869,393 1/1959 Hutchison 74516 A. HARRY LEVY, Primary Examiner. 

3. IN AN ENGINE DRIVEN VEHICLE HAVING A THROTTLE ADAPTED TO CONTROL THE SPEED THEREOF, LINKING MEANS CONNECTED TO THE THROTTLE, A LEVER PIVOTALLY MOUNTED IN THE VEHICLE AND CONNECTED TO SAID LINKING MEANS AND ADAPTED TO IMPART MOVEMENT THERETO, SAID LEVER HAVING A MULTIPLICITY OF SPACED CONTACT POINTS LOCATED THEREON, AN ACCELERATOR PEDAL PIVOTALLY MOUNTED IN THE VEHICLE, SAID PEDAL HAVING A MULTIPLICITY OF SPACED CONTACT POINTS LOCATED THEREON WHICH UPON PIVOTAL MOVEMENT OF SAID PEDAL SUCCESSIVELY BEAR AGAINST SAID CONTACT POINTS ON AN IMPART PIVOTAL MOVEMENT TO SAID LEVER WHEREBY A MULTIPLICITY OF RATIOS IS AVAILABLE FOR OPENING THE THROTTLE THROUGH SAID LINKING MEANS AND SAID LEVER FROM SAID PEDAL, AND RESILIENT MEANS LOCATED ON ONE OF SAID LEVER AND SAID PEDAL ADJACENT THE CONTACT POINTS THEREON WHICH UPON PIVOTAL MOVEMENT OF SAID PEDAL BEARS AGAINST A PORTION OF THE OTHER OF SAID LEVER AND SAID PEDAL ADAJCENT THE CONTACT POINTS THEREON TO PORVIDE A SMOOTH TRANSITION BETWEEN THE AVAILABLE RATIOS. 